Medical balloon assemblies are used for a variety of medical procedures including for the placement of medical devices, such as stents and stent grafts, for angioplasty procedures, for valvuloplasty procedures and so on.
The balloons of such assemblies are typically compliant or non-compliant. Complaint balloons may be made, for example, of polyurethane, Nylon, polyethylene and the like, while non-compliant balloons may be made of polyethylene terephthalate (PET), ultrahigh molecular weight polyethylene such as Dyneema™ and the like.
In order to maximise the wrappability of the balloon for delivery purposes, that it to minimise its folded and wrapped diameter, as well as to maximise its flexibility, the balloon wall is preferably made as thin as possible. This, however, results in a weaker balloon wall with increased chance of rupture of the balloon and limits the pressure to which the balloon can be inflated. Some balloon materials do not gain sufficient strength even with thicker balloon walls.
It is known to provide strengthening elements with such medical balloons, one known example being an embedded sleeve of woven or non-woven fibres in the polymer material forming the balloon. Strengthening elements of this type can provide high strength balloons less likely to tear or burst in use and which can be inflated to higher pressures. While strengthening sleeves can provide such enhancements, they lead to an increase in the overall thickness of the balloon wall and can also lead to an increase in the stiffness of the balloon, particularly when the balloon is deflated and when it is in its wrapped condition.
Examples of medical balloon assemblies having strengthening sleeves are disclosed in U.S.-2008/0033477, U.S.-2004/0082965, U.S.-2002/0098307, U.S.-2006/0085022, U.S.-2007/0219490 and U.S. Pat. No. 6,746,425.